People are people, but people interact differently depending on the country. Here in France, what we often hear about the USA is that they have very different social norm. The usual story is: someone goes to the USA, they are successful, everyone is nice with them, they have tons of friends, then suddenly something bad happens to the person, and all of their friends disappear/refuse to help. So from that I deduce that people in France in general (at least in my sphere) have less but deeper friendships. That's not a judgment of value of course, but that's one way countries can differ.